National Democrats have already spent tens of thousands of dollars aiding underdog Senate candidate Travis Childers, the moderate former congressman who hopes to make the Mississippi race competitive in the event that Republicans nominate insurgent conservative Chris McDaniel.

Childers has raised only a small sum of money for his race, just $82,000 all told, and reported having about $73,000 in his campaign account in mid-May.

Of that sum, nearly half comes from current or former Democratic lawmakers. Childers has collected $30,500 from sitting members of the U.S. Senate, including $5,000 PAC donations from Senate Majority Leader Harry Reid, New York Sen. Kirsten Gillbrand, Alaska Sen. Mark Begich and Colorado Sen. Michael Bennet, who chairs the Democratic Senatorial Campaign Committee.

It is not unusual for incumbent lawmakers to contribute to challengers the party has recruited. The investment in Childers — at a time of obvious financial scarcity for his campaign — represents an early move to prop up a candidate whose prospects depend heavily on the outcome of a June 24 GOP runoff election between McDaniel and incumbent Sen. Thad Cochran.

New Mexico Sen. Martin Heinrich has chipped in $2,500 through his PAC, while California Sen. Barbara Boxer and Indiana Sen. Joe Donnelly have given Childers $2,000 each through their leadership committees. In the first quarter of the year, Childers also received donations from PACs associated with Delaware Sen. Tom Carper and Montana Sen. Jon Tester.

Many of the donations are only now coming to light because Childers filed his pre-primary report late, which his campaign attributed to an error by his compliance firm. He was not listed in a Federal Election Commission release warning tardy filers.

On top of the support he has received from the Senate side, Childers also has collected several thousand dollars in donations from his former House colleagues, including several moderate Blue Dog Democrats like himself.

House Minority Whip Steny Hoyer’s PAC gave $2,500 to Childers and former Oklahoma Rep. Dan Boren’s PAC gave $1,000. Conservative former Democratic Rep. Walt Minnick cut a $1,000 check to his ex-colleague, while former North Dakota Rep. Earl Pomeroy gave $500 and former Reps. Allen Boyd of Florida and Michael Arcuri of New York contributed $250 each.